筑巢轻钢龙骨体系桁架梁试验研究及有限元分析  

EXPERIMENTAL INVESTIGATION AND FINITE ELEMENT ANALYSIS OF TRUSS BEAM OF NEST LIGHT-GAUGE STEEL SYSTEM

作　　者：王志军[1] 朱兰影[1] 余宾宁[1] 罗来安[1] 

机构地区：[1]山地城镇建设与新技术教育部重点实验室(重庆大学),重庆400045

出　　处：《工业建筑》2011年第12期111-115,共5页Industrial Construction

摘　　要：对5根采用蝶形连接件的不同构造形式的筑巢轻钢龙骨体系桁架梁进行承载力试验和有限元分析,研究筑巢轻钢桁架梁在竖向荷载作用下的受力特点、破坏模式、极限承载力及影响桁架梁抗弯刚度和极限承载力的主要因素。结果表明:桁架梁主要发生上弦端部或跨中的受弯或压弯破坏;减小第1个连接件距端部的距离或采用斜撑的方式会使桁架梁的破坏位置发生改变,但对承载力影响不大;增大上弦管的截面面积可以明显提高梁的极限承载力,但梁的抗弯刚度增长幅度不大;采用节点刚性假定模拟分析挠度误差较大,而考虑节点半刚性模型分析的结果与试验值更为接近;桁架梁主要由其跨中挠度控制设计,在正常使用阶段,桁架梁的承载力只为极限承载力的33%～45%。Through the bearing capacity test and finite element analysis of five nest light steel truss beams of different connection types,this paper made a study on the stress characteristics,failure mode and ultimate bearing capacity of nest light steel truss beam under vertical loads.The main factors which affect the flexural rigidity and ultimate bearing capacity of truss beam were also discussed.The result shows that the failure in truss beam mainly occurred at top chord near support or at mid-span due to the flexural or compression bending;the failure position will be changed by decreasing the distance between the first web member and support or using diagonal braces at the truss ends,but their effect on bearing capacity is not obvious;the ultimate bearing capacity of truss beam will be obviously increased after increasing cross section area of the top chord,but the change of bending stiffness of beams is little;the error of deflection simulation analysis is large with node rigid assumption,while results between simulation analysis and experimental values are more close with node semi-rigid assumption;the design of truss beam is mainly controlled by its mid-span deflection,the normal service bearing capacity of the truss beam can only reach 33~45 percent of ultimate bearing capacity.

关 键 词：轻钢龙骨体系 桁架梁 试验研究 半刚性连接 

分 类 号：TU392.5[建筑科学—结构工程]